Assessment of Water Quality in the Brokenhead River Watershed

Results and Discussion
Overview of the Brokenhead River Watershed
General Characteristics
The Brokenhead River watershed is located in southeast Manitoba, between the Red River
watershed to the west, and the Winnipeg River basin to the east. The Brokenhead River
watershed is more than 260,000 hectares (26,000 km 2 ) in size and originates approximately 40
km south of the Trans Canada highway (Hwy 1) in southern Manitoba. The river flows from
south to north, emptying into Lake Winnipeg. Close to its origin south of the Trans Canada
Highway, the river is indistinct (i.e., has no distinct channel), apparently flowing underground
for several kilometres. There are no primary flow control structures on the river, although there
are several low head dams, installed primarily for providing recreational opportunities (Donetz,
2002). The highest points in the watershed occur in the southern portion, at approximately
373m, sloping down to 216m near its terminus at Lake Winnipeg (AA-F and PFRA, 2004).
Figure 2 shows a Digital Elevation Model (DEM) of the watershed. The watershed encompasses
9 Rural Municipalities: Alexander, Brokenhead, Lac du Bonnet, Reynolds, Springfield, Ste.
Anne, St. Clements, Tache and Whitemouth. The population is mainly rural and farm-based.
Beausejour is the largest town, with smaller communities including Ste. Rita, Ross, Vivian,
Ladywood, Brokenhead Ojibway Naiton and Scanterbury.
The Brokenhead River watershed is located in two Ecozones. The western portion of the
watershed is found in the Boreal Plains Ecozone while the eastern portion is located in the Boreal
Shield Ecozone. Ecozones, which are further divided into Ecoregions and Ecodistricts, are a
terrestrial classification system developed to classify landscapes by integrating vegetation cover,
underlying geology, physiography, soils and climate (Smith et al., 1998). Ecozones are the
broadest categories of this classification system. In a similar manner, the western portion of the
Brokenhead River watershed is located in the Interlake Plain Ecoregion and the eastern portion
of the watershed is located in the Lake of the Woods Ecoregion (Figure 3). The Interlake Plain
Ecoregion is characterized by trees including trembling aspen and balsam poplar, with
understory vegetation including willow and red osier dogwood. Riverside (riparian) areas
contain Manitoba maple, green ash, elm and cottonwood. Much of the forest cover in this
Ecoregion has been significantly altered due to agriculture and urbanization. The Lake of the
Woods Ecoregion is characterized by extensive peatlands and associated organic soils, tree
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